Fuck speed

Fuck speed is the rate of motion between her pussy and his penis while fucking. It is measured in "Strokes Per Minute" or "SpM".
One fuck stroke is the complete cycle of one forth and back movement.
The fuck speed depends on the sex position, mood, age and many other things. The average fuck speed to start things is at around 40 SpM and the average fuck speed shortly before an orgasm is around 80 SpM.